Heater pumps for distilland heating with hot distillate

ABSTRACT

A pump pressurizes the heated hot sump distillate in the distillation process, distillate heating with hot distillate, thus leading to the reduction of overhead clearance requirements for the distiller.

May 29, 1973 c. T. suNDQUlsT HEATER PUMPS FOR DISTILLAND HEATING WITH HOT DISTILLATE Filed Deo. 4, 1970 INVENTOF? @MQ/QwQJ United States Patent O U.S. Cl. 202-236 1 Claim ABSTRACT F THE DISCLOSURE A pump pressurizes the heated hot sump distillate in the distillaiton process, distilland heating with hot distillate, thus leading to the reduction of overhead clearance requirements for the distiller.

This invention is an improvement to the distillation process, distilland heating with hot distillate. A pump pressurizes heated hot distillate to prevent vapor formation in the liquid. This eliminates the requirement that the liquid level in the condenser sump be elevated above the liquid level in the stratication column.

An object of the invention is the separation of a distillate from a solution.

An object of the invention is the reduction of the overhead clearance requirement for the distiller.

The gure is a flow diagram illustrating the invention.

Referring to the figure, temperature stratification column 50 is a tall vessel containing distillate tubes 98. The vessel and liquid contents have been preheated so that the top is hot and the bottom is cold. Then cold feed solution 9 is fed into the bottom of the column by solution pump 21. In the space surrounding the tubes cold feed solution 9 mixes into concentrated solution 11. The solution rises very slowly, being heated by the tubes. Vapor 4 separates from the solution at liquid surface 3. Part way up the column concentrated solution 11 is discharged. Vapor 4 passes from the column to condenser 51 and is condensed by direct contact with spray4 distillate 12.

Spray distillate 12 is a mixture of cold distillate 5 and hot sump distillate 6. It is sprinkled into the vapor space of condenser 51 through spray openings 86. Re circulating pump 23 maintains the ow of spray distillate through the spray openings sufficient to keep the temperatures of hot sump distillate 6 and Vapor 4 nearly the same. Splash defiector 84 confines the turblence caused by the falling spray to the top of the condenser sump.

A portion of the ow of hot sump distillate 6 is drawn olf by heater pump 26 and fed through distillate heater 53. From the heater heated hot sump distillate 14 ilows into the tops of distillate tubes 98. Heater pump 26, in combination with ow restriction 73 pressurizes heated hot sump distillate 14 to prevent vapor formation in the liquid.

Distillate flows very slowly downward inside distillate tubes 98 to distillate box 96. Downward velocities are kept very low so that a large temperature drop is realized by the descending distillate. Cold distillate ows to three-way control valve 63. Three-way control valve 63 alternately directs the ilow of coldy distillate to the bottom of the condenser sump and to spray openings 86 in the top of the condenser. Small distillate pump 25, pumping a little slower than the ow of cold distillate to threeway control valve 63, takes suction from the bottom of ice the condenser sump. Cold distillate form small distillate pump 25 continuously mixes with hot sump distillate 6 and ows .as distillate mixture 7 to the suction of recirculating pump 23. With this arrangement, cold distillate alternately ows into and out of the bottom of the condenser sump.

Pressure controller 68 has high and low pressure set points, where the control actions reverse. During pressure rise, the controller remotely operates three-Way control valve 63 to direct the cold distillate flow to the bottom of the condenser sump. At this time the ilow of distillate mitxure 7, alone, has insuiiicient cooling capacity to condense all of the ow of vapor 4. During pressure drop, pressure controller `68 remotely operates three-way control valve 63 to direct the cold distillate flow to spray openings 86 at the top of condenser 51. At this time the ilows of distillate mixture 7 and cold distillate 5, together, have more cooling capacity than necessary to condense the ilow of vapor 4.

Liquid level controller 66 senses increases in the quantity of distillate in the system at liquid surface L15. It corrects for these increases by remotely operating twoway control valve 61 to release product distillate 8 from the distiller. Liquid level controller 67 senses increases in the level of liquid surface 3. It corrects for these increases by remotely operating two-way control valve 62 to release concentrated solution 11 from the distiller.

Energy 10 is added to the system at a constant rate by the distillate heater 53 and pump motors. Energy is lost by heat carried away with the concentrated solution, by heat carriedI away with the product distillate and by heat transmission through walls of vessels and piping. Insulation 55 minimizes heat transmission through walls.

Referring to the figure, total energy in the system is controlled by temperature controller 69, which has high and low temperature set points, where control actions reverse. During temperature rise, the controller remotely operates ilow control 64 to reduce the ilow of cold feed solution 9. This causes a reduction in the flow of concentrated solution 11 through two-way control valve 62 and consequently a reduction in heat being lost from the system. During temperature drop, temperature controller 69 remotely operates flow control 64 to increase the ow of cold feed solution 9. This causes an increase in the flow of concentrated solution l11 through two-way control valve 62 and consequently an increase in heat being lost from the system.

What is claimed is:

1. A distiller for separating distillate from a solution including the following: means ilowing cold feed solution into the bottom of the space surrounding a vertical distillate tube in a temperature stratification column, cold feed solution mixing into cool concentrated solution in said space; said distillate tube heating said concentrated solution; means passing concentrated solution from the temperature stratification column at an elevated position out of the distiller; means separating vapor from concentrated solution at its liquid surface in said ternperature stratification column; means passing vapor from said temperature stratification column to the vapor spade in a vertical condenser chamber having a sump in its lower portion; hot sump distillate accumulating in the upper part of said condenser sump; means permitting hot sump distillate to pass through a distillate heater and leaving as heated hot sump distillate; means passing said heated hot sump distillate to the top of said distillate tube; a pump pressurizing said heated hot sump distillater to flow as indicated; said heated hot sfump distillate being cooled as it descends in said distillate tube and exiting as cold distillate; conduit means conducting said cold distillate from said distillate tube bottom to the lower part of said condenser sump and to vapor contacting means in said vapor space in said condenser; means withdrawing cold distillate from said lower part of said condenser sump and feeding it to said contacting means in said vapor space in said condenser; further conduit means passing cold distillate from the first mentioned conduit as product distillate; a restriction oriice in the first mentioned conduit meansconveying the cold distillate exiting from said distillate tube; said pumps and said restriction orice cooperating to pressurize said heated hot sump distillate to prevent vapor formation in the liquid.

References Cited UNITED STATES PATENTS 2,015,680 lll/1935 `Kermer 159-31 2,570,213 10/1951 Cross 159'-22 A X 3,444,050 5/1969 Sundquist 203-11 X 2,572,321 10/1951 Dreanesly ..v.. 15947 2,868,280 1/1959 Sargent et al. 159-47 3,545,518 12/1970 Kohlmann 159-2 R NORMAN YUDKOFF, Primary Examiner I. SOFER, Assistant Examiner U.S. Cl. X.R.

2021-185 A; 203-11; l59-DIG. 17 

